Ctenophora

Animals of the phylum ctenophora, often called comb jellies, are oceanic jelly-like organisms distinguished by their eight "comb rows" of cilia used for movement. The term ctenophora means "comb bearer" in Latin. While ctenophores are poorly understood, the beautiful creatures have received increasing attention due to their exhibition in aquariums around the world. One of the amazing things about cnidaria is that their beating cilia act as diffraction gratings, causing the animals to display a rainbow of colors.

In the fairly recent past, the phyla ctenophora and cnidiaria were lumped into one--coelenterata. Now the prevailing view among taxonomists is that the coelenterates are sufficiently different to necessitate two phyla. Unlike cnidarians, ctenophores do not inherently possess nematocysts (stinging cells). Some ctenophores possess and use stinging cells, but these are obtained by eating cnidarians. Most ctenophores capture prey with sticky cells called colloblasts. A few ctenophores have special cilia in their mouths that can pierce into gelatinous prey. All ctenophores are carnivorous and are the prey of jellyfish, sea turtles, and fish.

There are probably about 100-150 species of ctenophores. The study of phylum ctenophora has been limited for several reasons. Though lovely, the animals don't seem all that important. They are small and inconspicuous. Many, particularly those in the deep ocean, are incredibly fragile, making them difficult to capture and resulting in scarce fossil records.